package com.server.controller;

import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;

import javax.imageio.ImageIO;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

@Controller("codeController")
@RequestMapping("code")
public class CodeController {
	private int width = 120; //定义图片的宽
	private int height = 50;//定义图片的高
	private int codeCount = 4;//定义图片上显示验证码的个数
	private int xx = 20;
	private int fontHeight = 30;
	private int codeY = 30;
	char[] ch="ABCDEGHIJKlLMNOPQRSTU0123VWXYZabcde789fghijklmnopqrstuvwxyz456".toCharArray(); 
	
	@RequestMapping("getCode")
	public void getCode(HttpServletRequest request,HttpServletResponse response,HttpSession session) throws
	 IOException{
		//定义图像buffer
		BufferedImage buffImg = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
		
		Graphics gd = buffImg.getGraphics();
		//创建一个随机数生成器类
		Random random = new Random();
		
		gd.setColor(java.awt.Color.WHITE);
		gd.fillRect(0, 0, width, height);
		//创建字体，字体的大小应该根据图片的高度来定
		Font font = new Font("Fixedsys",Font.BOLD,fontHeight);
		//设置字体
		gd.setFont(font);
		
		//画边框
		gd.setColor(java.awt.Color.BLACK);
		gd.drawRect(0, 0, width-1, height-1);
		
		//随机产生40条干扰线，图像中的认证码不易被其他程序探测
		gd.setColor(java.awt.Color.BLACK);
		for(int i = 0;i < 40;i++){
			int x = random.nextInt(width);
			int y = random.nextInt(height);
			int x1 = random.nextInt(20);
			int y1 = random.nextInt(20);
			gd.drawLine(x, y, x+x1, y+y1);
			
		}
		
		//randomCode用于保存随机产生的验证码，以便用户登录验证
		
		StringBuffer randomCode = new StringBuffer();
		int red = 0, green = 0, blue = 0,len = ch.length,index;
		//随机产生验证码
		for(int i = 0;i < codeCount; i++){
			index = random.nextInt(len);
			char code = ch[index];
			/*
			// 产生随机的颜色分量来构造颜色值，这样输出的每位数字的颜色值都将不同。
		      red = random.nextInt(255);
		      green = random.nextInt(255);
		      blue = random.nextInt(255);
		      // 用随机产生的颜色将验证码绘制到图像中。
		      */
		      gd.setColor(new java.awt.Color(0,0,0));
		      gd.drawString(code+"", (i + 1) * xx, codeY);
		   // 将产生的四个随机数组合在一起。
		      randomCode.append(code);
		}
		// 将四位数字的验证码保存到Session中。
	   // System.out.print(randomCode);
	    session.setAttribute("code", randomCode.toString());

	    // 禁止图像缓存。
	    response.setHeader("Pragma", "no-cache");
	    response.setHeader("Cache-Control", "no-cache");
	    response.setDateHeader("Expires", 0);

	    response.setContentType("image/jpeg");

	    // 将图像输出到Servlet输出流中。
	    ServletOutputStream sos = response.getOutputStream();
	    ImageIO.write(buffImg, "jpeg", sos);
	    sos.close();
		
	}
}
